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EQ ADVISORS TRUST

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EQ/JPMorgan Growth Allocation Portfolio – Class IB and K Shares

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Seeks to achieve long-term capital appreciation with an emphasis on risk-adjusted returns and managing volatility in the Portfolio.

Expense Narrative [Text Block]

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The following table describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio. The table below does not reflect any fees and expenses associated with variable life insurance contracts and variable annuity certificates and contracts (“Contracts”), which would increase overall fees and expenses. See the Contract prospectus for a description of those fees and expenses.

Operating Expenses Caption [Text]

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Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

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PORTFOLIO TURNOVER

Portfolio Turnover, Rate

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14.00%

Expense Example Narrative [Text Block]

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This Example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other portfolios. The Example assumes that you invest $10,000 in the Portfolio for the periods indicated, that your investment has a 5% return each year, that the Portfolio’s operating expenses remain the same, and that the Expense Limitation Arrangement is not renewed. This Example does not reflect any Contract-related fees and expenses including redemption fees (if any) at the Contract level. If such fees and expenses were reflected, the total expenses would be higher. Although your actual costs may be higher or lower, based on these assumptions, whether you redeem or hold your shares, your costs would be:

Strategy Narrative [Text Block]

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Under normal market conditions, the Portfolio will invest primarily in a combination of exchange-traded funds (“ETFs”), futures contracts, and individual equity and fixed income securities that provide exposure to global equity markets and U.S. Treasuries. By adjusting investment exposure among the various equity and fixed income asset classes in the Portfolio, the Sub-Adviser will attempt to reduce overall portfolio volatility and mitigate the effects of extreme market environments, without sacrificing long-term returns. The Portfolio may gain or adjust exposure to each asset class either through transactions in individual securities or through other instruments, including derivatives.

Strategic Long-Term Asset Allocation. Under normal market conditions, it is expected that the Portfolio’s strategic long-term asset allocation will be approximately 65% in equity securities (or financial instruments that provide investment exposure to such securities) and approximately 35% in fixed income securities (or financial instruments that provide investment exposure to such securities), including cash equivalents. The actual percentage allocations at any time may vary. In monitoring and strategically adjusting the Portfolio’s exposures and weightings among the various asset classes, the Sub-Adviser draws on the quantitative analysis and qualitative insights produced by dedicated research and strategy teams that support the investment process.

Risk Managed Asset Allocation. The Sub-Adviser may decrease the Portfolio’s equity exposure to 20% or less of net assets, and may increase the Portfolio’s fixed income exposure to 80% or more of net assets, based on a quantitatively-driven risk management framework, described below. However, under normal market conditions, the Portfolio’s net allocation to equity or fixed income securities will not increase or decrease by more than 5% of net assets in a day.

Equity Asset Classes. The Portfolio’s equity allocation will be invested in the following equity asset classes: U.S. Large Cap Equity, U.S. Small Cap Equity, United Kingdom Equity, European Equity, and Japanese Equity. The Portfolio’s equity investments will be allocated among discrete portions of the Portfolio that will invest in securities included in the Standard & Poor’s 500 Composite Stock Index (“S&P 500 Index”), the Russell 2000 Index (“Russell 2000 Index”), the FTSE 100 Index, the DJ EuroSTOXX 50 Index, and the TOPIX Index, respectively, and in ETFs and futures contracts that provide exposure to these indexes and substantially similar indexes. The Portfolio will invest in these securities and other instruments in a manner that is intended to track the performance (before fees and expenses) of the relevant index. As of December 31, 2019, the market capitalization of companies in the S&P 500 Index, which consists of common stocks of 500 of the largest U.S. companies, ranged from $4.6 billion to $1,305 billion; in the Russell 2000 Index, which tracks the performance of approximately 2000 of the smallest companies in the Russell 3000 Index, from $12.7 million to $8.3 billion; in the FTSE 100 Index, which represents the performance of the 100 largest UK-domiciled blue chip companies, from $4.9 billion to $231.4 billion; in the DJ EuroSTOXX 50 Index, which represents the performance of the 50 largest companies in 11 Eurozone countries, from $20.9 billion to $235.1 billion; and in the TOPIX Index, which comprises all companies listed on the First Section of the Tokyo Stock Exchange, from $23.4 million to $231.2 billion (approximately 2080 constituents). Each of these indexes is weighted by market capitalization. The Sub-Adviser may allocate the Portfolio’s investments among these indices based on its assessment of risk in the equity markets relative to potential return.

Fixed Income Asset Class. The Portfolio’s fixed income allocation will be invested in the U.S. Treasuries asset class. The Portfolio’s fixed income investments will consist primarily of investments in securities included in the Bloomberg Barclays Intermediate U.S. Treasury Index and in ETFs and futures contracts that provide exposure to the index. The Portfolio will invest in these securities and other instruments in a manner that is intended to track the performance (before fees and expenses) of the index. The Bloomberg Barclays Intermediate U.S. Treasury Index is a market-value weighted index that measures U.S. dollar-denominated, fixed rate, nominal debt issued by the U.S. Treasury with maturities of 1 to 9.9999 years to maturity.

Indexing Strategy. The Portfolio uses a strategy that is commonly referred to as an indexing strategy. The Portfolio may use a replication technique or sampling approach to execute its indexing strategy. Circumstances under which the Sub-Adviser may use a sampling approach to execute the indexing strategy include when there are practical difficulties or substantial costs involved in compiling a portfolio of securities to track the performance (before fees and expenses) of the relevant index; where the relevant index contains component securities too numerous to purchase or sell efficiently; or in instances when a component security becomes temporarily illiquid, unavailable, or less liquid. The quantity of holdings in the Portfolio will be based on a number of factors, including the asset size of the Portfolio. Each index sponsor has its own method for periodically rebalancing the index by adding, removing or rebalancing the index components to take into account market changes.

Risk Management Framework. The risk management framework integrates quantitative momentum and volatility models and signals to make systematic adjustments to the Portfolio’s strategic long-term asset allocation in order to determine a risk managed asset allocation.

Momentum Indicators. Momentum is the tendency of investments to exhibit persistence in their performance. The Sub-Adviser uses momentum signals to identify adverse market environments. The Sub-Adviser believes that negative momentum indicates future periods of negative investment returns and increased volatility. When negative momentum deteriorates below a pre-set threshold determined by the Sub-Adviser based on its proprietary momentum-based model, the Sub-Adviser will reduce, sometimes significantly, the Portfolio’s exposure to the particular asset class exhibiting the negative momentum. To reduce the Portfolio’s exposure to a particular asset class, the Sub-Adviser will primarily use derivatives, but may also sell physical securities. The Sub-Adviser may reduce the Portfolio’s exposure to a particular asset class to 0% if the momentum indicator becomes sufficiently negative for that asset class. The Sub-Adviser will reestablish the Portfolio’s exposure to an asset class once the market environment improves and momentum strengthens to surpass a pre-set threshold determined by the Sub-Adviser based on its proprietary model.

Volatility Indicators. Volatility is a statistical measure of the magnitude of changes in the Portfolio’s returns, without regard to the direction of those changes. Higher volatility generally indicates higher risk and is often reflected by frequent and sometimes significant movements up and down in value. To implement volatility management, the Sub-Adviser will monitor forecasted annualized volatility of the Portfolio’s returns, placing a greater weight on recent historic data. When the forecasted volatility is expected to exceed a pre-set threshold determined by the Sub-Adviser based on its proprietary volatility-based model, the Sub-Adviser will attempt to reduce the volatility below the threshold. To attempt to reduce the volatility, the Sub-Adviser will primarily use derivatives, but may also sell physical securities. The Sub-Adviser may use these methods as often as daily to reduce the Portfolio’s expected volatility level. Due to market conditions or other factors, the actual or realized volatility of the Portfolio for any particular period of time may be materially above or below the pre-set threshold. During such times, the Portfolio’s overall equity exposure may deviate significantly from its strategic asset allocation and could be substantially less than 65% of the Portfolio’s assets (and could be 0%). Volatility management techniques may reduce potential losses and/or mitigate financial risks to insurance companies that provide certain benefits and guarantees available under the Contracts and offer the Portfolio as an investment option in their products.

Use of Derivative Instruments. The Portfolio may invest in derivative instruments, including futures contracts and other instruments, for a variety of purposes, including as a means to manage equity and fixed income exposure (including for purposes of implementing the risk management framework) without having to purchase or sell underlying investments. For example, when the level of market volatility is increasing, the Sub-Adviser may attempt to limit the Portfolio’s equity exposure by closing existing long exchange-traded futures contracts, selling exposures that are derived using ETFs, shorting or selling long futures positions on an index or, in the case where physical securities are held, selling exchange-traded futures contracts. The Portfolio may also invest in derivative instruments to seek enhanced returns from certain asset classes. The Portfolio may use index futures, for example, to gain broad exposure to a particular segment of the market, while buying representative securities to achieve exposure to another. The Sub-Adviser will choose in each case based on considerations of cost and efficiency of access to the desired investment exposure. It is anticipated that the Portfolio’s derivative instruments will consist primarily of exchange-traded equity index, U.S. Treasury and currency futures. The Portfolio may also invest in currency forwards. The Portfolio’s holdings may be frequently adjusted to reflect the Sub-Adviser’s assessment of changing risks, which could result in high portfolio turnover. The Sub-Adviser believes that these adjustments also can frequently be made efficiently and economically through the use of derivative strategies.

The Portfolio may invest in derivatives to the extent permitted by applicable law. It is anticipated that the Portfolio’s use of derivatives will be consistent with its overall investment strategy of obtaining and managing exposure to various asset classes. Because the Portfolio will use derivatives to obtain and manage the Portfolio’s exposure to different asset classes, the Portfolio’s use of derivatives may be substantial. The Portfolio’s investments in derivatives may be deemed to involve the use of leverage because the Portfolio is not required to invest the full market value of the contract upon entering into the contract but participates in gains and losses on the full contract price. In addition, the Portfolio’s investments in derivatives may be deemed to involve the use of leverage because the heightened price sensitivity of some derivatives to market changes may magnify the Portfolio’s gain or loss. It is not generally expected, however, that the Portfolio will be leveraged by borrowing money for investment purposes.

From time to time or potentially for extended periods of time in periods of continued market distress, the Portfolio may maintain a considerable percentage of its total assets in cash and cash equivalent instruments as margin or collateral for the Portfolio’s obligations under derivative transactions, to implement the risk management strategies, and for other portfolio management purposes. The larger the value of the Portfolio’s derivative positions, as opposed to positions held in non-derivative instruments, the more the Portfolio will be required to maintain cash and cash equivalents as margin or collateral for such derivatives.

Risk Narrative [Text Block]

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An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The value of your investment may fall, sometimes sharply, and you could lose money by investing in the Portfolio. There can be no assurance that the Portfolio will achieve its investment objective.

The following risks can negatively affect the Portfolio’s performance. The most significant risks are listed first, followed by additional risks in alphabetical order.

Volatility Management Risk: Although the Sub-Adviser’s risk management framework is intended to moderate the Portfolio’s volatility and thereby reduce the overall risk of investing in the Portfolio, it may not work as intended and may result in losses by the Portfolio or periods of underperformance, including during periods when market values are increasing but market volatility is high or when the Portfolio has reduced its equity exposure but market changes do not impact equity returns adversely to the extent predicted by the Sub-Adviser. Because the characteristics of many securities change as markets change or time passes, the result of the risk management framework will be subject to the Sub-Adviser’s ability to continually recalculate, readjust, and execute volatility management techniques (such as using futures to manage equity exposure) in an efficient manner. The result of the risk management framework also will be subject to the Sub-Adviser’s ability to correctly assess future market conditions as indicated by momentum signals. In addition, market conditions change, sometimes rapidly and unpredictably, and the Sub-Adviser may be unable to execute the strategy in a timely manner or at all. The risk management framework incorporates quantitative models and signals. If those models or signals prove to be flawed or for other reasons do not produce the desired results, any decisions based on the models or signals may expose the Portfolio to additional risks and losses. The use of models has inherent risks, and the success of relying on or otherwise using a model depends, among other things, on the accuracy and completeness of the model’s development, implementation and maintenance; on the model’s assumptions and methodologies; and on the accuracy and reliability of the inputs and output of the model. The Sub-Adviser from time to time may make changes to its models or signals that do not require shareholder notice. Moreover, volatility management techniques may expose the Portfolio to costs, such as increased portfolio transaction costs, which could cause or increase losses or reduce gains. In addition, the use of derivatives in connection with the risk management framework may expose the Portfolio to different and potentially greater risks than if it had only invested in the underlying investments. Futures contracts and other instruments used in connection with the risk management framework are not necessarily held by the Portfolio to hedge the value of the Portfolio’s other investments and, as a result, these futures contracts and other instruments may decline in value at the same time as the Portfolio’s other investments. The Portfolio’s performance may be lower than the performance of similar funds where volatility management techniques are not used.

ETFs Risk: The Portfolio’s shareholders will indirectly bear fees and expenses paid by the ETFs in which it invests, in addition to the Portfolio’s direct fees and expenses. The cost of investing in the Portfolio, therefore, may be higher than the cost of investing in a mutual fund that invests directly in individual stocks and bonds. In addition, the Portfolio’s net asset value will be subject to fluctuations in the market values of the ETFs in which it invests. The Portfolio is also subject to the risks associated with the securities or other investments in which the ETFs invest, and the ability of the Portfolio to meet its investment objective will directly depend on the ability of the ETFs to meet their investment objectives. An index-based ETF’s performance may not match that of the index it seeks to track. An actively managed ETF’s performance will reflect its adviser’s ability to make investment decisions that are suited to achieving the ETF’s investment objective. It is also possible that an active trading market for an ETF may not develop or be maintained, in which case the liquidity and value of the Portfolio’s investment in the ETF could be substantially and adversely affected. The extent to which the investment performance and risks associated with the Portfolio correlate to those of a particular ETF will depend upon the extent to which the Portfolio’s assets are allocated from time to time for investment in the ETF, which will vary.

Asset Allocation Risk: The Portfolio’s investment performance depends upon how its assets are allocated across various asset classes and how its assets are invested within those asset classes. Some asset classes and investments may perform below expectations or the securities markets generally over short and extended periods. The allocation strategies used and the allocation and investment decisions made could cause the Portfolio to lose value and may not produce the desired results.

Government Securities Risk: Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. government. Some obligations are backed only by the credit of the issuing agency or instrumentality, and, in some cases, there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security the Portfolio holds does not apply to the market value of the security or to shares of the Portfolio. A security backed by the U.S. Treasury or the full faith and credit of the U.S. government is guaranteed only as to the timely payment of interest and principal when held to maturity.

Index Strategy Risk: The Portfolio (or a portion thereof) employs an index strategy and generally will not modify its index strategy to respond to changes in market trends or the economy, which means that the Portfolio may be particularly susceptible to a general decline in the market segment relating to the relevant index. In addition, although the index strategy attempts to closely track the relevant index, the Portfolio may not invest in all of the securities in the index. Therefore, there can be no assurance that the performance of the index strategy will match that of the relevant index. To the extent the Portfolio utilizes a representative sampling approach, it may experience tracking error to a greater extent than if the Portfolio sought to replicate the index.

Derivatives Risk: The Portfolio’s investments in derivatives may rise or fall in value more rapidly than other investments and may reduce the Portfolio’s returns and increase the volatility of the Portfolio’s net asset value. Investing in derivatives involves investment techniques and risk analyses different from, and risks in some respects greater than, those associated with investing in more traditional investments, such as stocks and bonds. Derivatives may be leveraged such that a small investment can have a significant impact on the Portfolio’s exposure to stock market values, interest rates, or other investments. As a result, a relatively small price movement in a derivatives contract may cause an immediate and substantial loss, and the Portfolio could lose more than the amount it invested. Some derivatives can have the potential for unlimited losses. In addition, it may be difficult or impossible for the Portfolio to purchase or sell certain derivatives in sufficient amounts to achieve the desired level of exposure, or to terminate or offset existing arrangements, which may result in a loss or may be costly to the Portfolio. Some derivatives are more sensitive to market price fluctuations and to interest rate changes than other investments. Derivatives may not behave as anticipated by the Portfolio, and derivatives strategies that are successful under certain market conditions may be less successful or unsuccessful under other market conditions. The Portfolio also may be exposed to losses if the counterparty in the transaction is unable or unwilling to fulfill its contractual obligation. In certain cases, the Portfolio may be hindered or delayed in exercising remedies against or closing out derivatives with a counterparty, resulting in additional losses. Derivatives also may be subject to the risk of mispricing or improper valuation. Derivatives can be difficult to value, and valuation may be more difficult in times of market turmoil. Changing regulation may make derivatives more costly, limit their availability, impact the Portfolio’s ability to maintain its investments in derivatives, disrupt markets, or otherwise adversely affect their value or performance.

Cash Management Risk: Upon entering into certain derivatives contracts, such as futures contracts, and to maintain open positions in certain derivatives contracts, the Portfolio may be required to post collateral for the contract, the amount of which may vary. In addition, the Portfolio may maintain cash and cash equivalent positions as part of the Portfolio’s strategy in order to take advantage of investment opportunities as they arise, to manage the Portfolio’s market exposure and for other portfolio management purposes. As such, the Portfolio may maintain cash balances, which may be significant, with counterparties such as the Trust’s custodian or its affiliates. Maintaining larger cash and cash equivalent positions could negatively affect the Portfolio’s performance due to missed investment opportunities and may also subject the Portfolio to additional risks, such as increased credit risk with respect to the custodian bank holding the assets and the risk that a counterparty may be unable or unwilling to honor its obligations.

Credit Risk: The Portfolio is subject to the risk that the issuer or guarantor of a fixed income security, or the counterparty to a transaction, is unable or unwilling, or is perceived as unable or unwilling, to make timely interest or principal payments, or otherwise honor its obligations, which may cause the Portfolio’s holdings to lose value. The downgrade of a security’s credit rating may decrease its value. Lower credit quality also may lead to greater volatility in the price of a security and may negatively affect a security’s liquidity. The credit quality of a security can deteriorate suddenly and rapidly.

Equity Risk: In general, the values of stocks and other equity securities fluctuate, and sometimes widely fluctuate, in response to changes in a company’s financial condition as well as general market, economic and political conditions and other factors.

Foreign Securities Risk: Investments in foreign securities involve risks in addition to those associated with investments in U.S. securities. Foreign markets, particularly emerging markets, may be less liquid, more volatile and subject to less government supervision and regulation than U.S. markets, and it may take more time to clear and settle trades involving foreign securities, which could negatively impact the Portfolio’s investments and cause it to lose money. Security values also may be negatively affected by changes in the exchange rates between the U.S. dollar and foreign currencies. Differences between U.S. and foreign legal, political and economic systems, regulatory regimes and market practices, as well as trade barriers and other protectionist trade policies (including those of the U.S.), governmental instability, or other political or economic actions, also may adversely impact security values. World markets, or those in a particular region, may all react in similar fashion to important economic or political developments. Events and evolving conditions in certain economies or markets may alter the risks associated with investments tied to countries or regions that historically were perceived as comparatively stable and make such investments riskier and more volatile. Regardless of where a company is organized or its stock is traded, its performance may be significantly affected by events in regions from which it derives its profits or in which it conducts significant operations.

Currency Risk: Investments that are denominated in or that provide exposure to foreign currencies are subject to the risk that those currencies will decline in value relative to the U.S. dollar. Any such decline may erode or reverse any potential gains from an investment in securities denominated in foreign currency or may widen existing loss. In the case of hedging positions, there is the risk that the U.S. dollar will decline in value relative to the currency being hedged. Currency rates may fluctuate significantly over short periods of time.

European Economic Risk: The economies of European Union (“EU”) member countries and their trading partners, as well as the broader global economy, may be adversely affected by changes in the euro’s exchange rate, changes in EU or governmental regulations on trade, and the threat of default or an actual default by an EU member country on its sovereign debt, which could negatively impact the Portfolio’s investments and cause it to lose money. The United Kingdom (“UK”) left the EU on January 31, 2020, commonly referred to as “Brexit.” The effect on the UK’s economy will likely depend on the nature of trade relations with the EU following its exit, a matter that is being negotiated. There is significant market uncertainty regarding Brexit’s ramifications, and the range and potential implications of possible political, regulatory, economic, and market outcomes cannot be fully known. The negative impact on not only the UK and European economies but also the broader global economy could be significant, potentially resulting in increased volatility and illiquidity, which could adversely affect the value of the Portfolio’s investments. Any further withdrawals from the EU could cause additional market disruption globally.

Geographic Concentration Risk: To the extent the Portfolio invests a significant portion of its assets in securities of companies domiciled, or exercising the predominant part of their economic activity, in one country or geographic region, it assumes the risk that economic, political, social and environmental conditions in that particular country or region will have a significant impact on the Portfolio’s investment performance and that the Portfolio’s performance will be more volatile than the performance of more geographically diversified funds.

Futures Contract Risk: The primary risks associated with the use of futures contracts are (a) the imperfect correlation between the change in market value of the instruments held by the Portfolio and the price of the futures contract; (b) liquidity risks, including the possible absence of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (c) losses (potentially unlimited) caused by unanticipated market movements; (d) an investment manager’s inability to predict correctly the direction of securities prices, interest rates, currency exchange rates and other economic factors; (e) the possibility that a counterparty, clearing member or clearinghouse will default in the performance of its obligations; (f) if the Portfolio has insufficient cash, it may have to sell securities from its portfolio to meet daily variation margin requirements, and the Portfolio may have to sell securities at a time when it may be disadvantageous to do so; and (g) transaction costs associated with investments in futures contracts may be significant, which could cause or increase losses or reduce gains. Futures contracts are also subject to the same risks as the underlying investments to which they provide exposure. In addition, futures contracts may subject the Portfolio to leveraging risk.

Interest Rate Risk: Changes in interest rates may affect the yield, liquidity and value of investments in income producing or debt securities. Changes in interest rates also may affect the value of other securities. When interest rates rise, the value of the Portfolio’s debt securities generally declines. Conversely, when interest rates decline, the value of the Portfolio’s debt securities generally rises. Typically, the longer the maturity or duration of a debt security, the greater the effect a change in interest rates could have on the security’s price. Thus, the sensitivity of the Portfolio’s debt securities to interest rate risk will increase with any increase in the duration of those securities. A significant or rapid rise in interest rates could result in losses to the Portfolio.

Investment Grade Securities Risk: Securities rated in the lower investment grade rating categories (e.g., BBB or Baa) are considered investment grade securities, but are somewhat riskier than higher rated obligations because they are regarded as having only an adequate capacity to pay principal and interest, are considered to lack outstanding investment characteristics, and may possess certain speculative characteristics.

Large-Cap Company Risk: Larger, more established companies may be unable to respond quickly to new competitive challenges such as changes in technology and consumer tastes, which may lead to a decline in their market price. Many larger companies also may not be able to attain the high growth rate of successful smaller companies, especially during extended periods of economic expansion.

Leveraging Risk: When the Portfolio leverages its holdings, the value of an investment in the Portfolio will be more volatile and all other risks will tend to be compounded. Investments that create leverage can result in losses to the Portfolio that exceed the amount originally invested and may accelerate the rate of losses (some of which may be sudden or substantial). For certain investments that create leverage, relatively small market fluctuations can result in large changes in the value of such investments. There can be no assurance that the Portfolio’s use of any leverage will be successful.

Market Risk: The Portfolio is subject to the risk that the securities markets will move down, sometimes rapidly and unpredictably, based on overall economic conditions and other factors, which may negatively affect Portfolio performance. Securities markets also may experience long periods of decline in value. Changes in the financial condition of a single issuer can impact a market as a whole. Geo-political risks, including terrorism, tensions or open conflict between nations, or political or economic dysfunction within some nations that are major players on the world stage, may lead to instability in world economies and markets, may lead to increased market volatility, and may have adverse long-term effects. Events such as natural disasters or pandemics, and governments’ reactions to such events, could cause uncertainty in the markets and may adversely affect the performance of the global economy. In addition, markets and market participants are increasingly reliant on information data systems. Inaccurate data, software or other technology malfunctions, programming inaccuracies, unauthorized use or access, and similar circumstances may impair the performance of these systems and may have an adverse impact upon a single issuer, a group of issuers, or the market at-large.

Mid-Cap and Small-Cap Company Risk: Mid-cap and small-cap companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies, all of which can negatively affect their value. In general, these risks are greater for small-cap companies than for mid-cap companies.

New Portfolio Risk: The Portfolio is newly or recently established and has limited operating history. The Portfolio may not be successful in implementing its investment strategy, and there can be no assurance that the Portfolio will grow to or maintain an economically viable size, which could result in the Portfolio being liquidated at any time without shareholder approval and at a time that may not be favorable for all shareholders. Until the Portfolio is fully capitalized, it may be unable to pursue its investment objective or execute its principal investment strategies.

Portfolio Management Risk: The Portfolio is subject to the risk that strategies used by an investment manager and its securities selections fail to produce the intended results. An investment manager’s judgments or decisions about the quality, relative yield or value of, or market trends affecting, a particular security or issuer, industry, sector, region or market segment, or about the economy or interest rates, may be incorrect or otherwise may not produce the intended results, which may result in losses to the Portfolio. In addition, many processes used in Portfolio management, including security selection, rely, in whole or in part, on the use of various technologies. The Portfolio may suffer losses if there are imperfections, errors or limitations in the quantitative, analytic or other tools, resources, information and data used, or the analyses employed or relied on, by an investment manager, or if such tools, resources, information or data are used incorrectly, fail to produce the desired results, or otherwise do not work as intended. There can be no assurance that the use of these technologies will result in effective investment decisions for the Portfolio.

Portfolio Turnover Risk: High portfolio turnover (generally, turnover in excess of 100% in any given fiscal year) may result in increased transaction costs to the Portfolio, which may result in higher fund expenses and lower total return.

Redemption Risk: The Portfolio may experience periods of heavy redemptions that could cause the Portfolio to sell assets at inopportune times or at a loss or depressed value. Redemption risk is heightened during periods of declining or illiquid markets. Heavy redemptions could hurt the Portfolio’s performance.

Market developments and other factors, including a general rise in interest rates, have the potential to cause investors to move out of fixed income securities on a large scale, which may increase redemptions from mutual funds that hold large amounts of fixed income securities. The market-making capacity of dealers has been reduced in recent years, in part as a result of structural changes, such as fewer proprietary trading desks at broker-dealers and increased regulatory capital requirements. In addition, significant securities market disruptions related to outbreaks of the coronavirus disease (COVID-19) have led to dislocation in the market for a variety of fixed income securities (including, without limitation, commercial paper, corporate debt securities, certificates of deposit, asset-backed debt securities and municipal obligations), which has decreased liquidity and sharply reduced returns. Increased redemptions from mutual funds that hold large amounts of fixed income securities, coupled with a reduction in the ability or willingness of dealers and other institutional investors to buy or hold fixed income securities, may result in decreased liquidity and increased volatility in the fixed income markets.

Sector Risk: From time to time, based on market or economic conditions, the Portfolio may have significant positions in one or more sectors of the market. To the extent the Portfolio invests more heavily in particular sectors, its performance will be especially sensitive to developments that significantly affect those sectors. Individual sectors may be more volatile, and may perform differently, than the broader market. The industries that constitute a sector may all react in the same way to economic, political or regulatory events.

Risk Not Insured Depository Institution [Text]

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An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Performance Narrative [Text Block]

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The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio’s performance from year to year and by showing how the Portfolio’s average annual total returns for the past one-year and since inception periods through December 31, 2019 compared to the returns of a broad-based securities market index. The additional broad-based securities market index and the hypothetical composite index show how the Portfolio’s performance compared with the returns of other asset classes in which the Portfolio may invest. Past performance is not an indication of future performance.

The performance results do not reflect any Contract-related fees and expenses, which would reduce the performance results.

After the close of business on September 4, 2019, operations for Class K ceased and shares were fully redeemed.

Performance Additional Market Index [Text]

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The additional broad-based securities market index and the hypothetical composite index show how the Portfolio’s performance compared with the returns of other asset classes in which the Portfolio may invest.

Bar Chart [Heading]

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Calendar Year Annual Total Returns — Class IB